1. Field of the Invention
The present invention relates to a light-emitting device provided with a phosphor kneaded matter obtained from a phosphor kneaded matter packaging container in which a phosphor and resin and the like are kneaded, and a method for manufacturing the same.
2. Description of the Background Art
A light-emitting device in which a semiconductor light-emitting element and a phosphor are combined with each other has drawn public attentions as a light-emitting device of the next generation that can achieve low power-consumption, small-size and high-luminance, as well as color reproducibility in a wide range, and researches and developments have been vigorously carried out thereon. Here, primary light to be emitted from the light-emitting element is normally selected from a long wavelength range from ultraviolet rays to blue rays, that is, from 380 to 480 nm, and is utilized. Moreover, wavelength converting units using various phosphors suitable for this application have been proposed.
With respect to a tetravalent manganese-activated fluoride metal salt phosphor, for example, U.S. Patent Application Publication No. 2006/0169998 has described its manufacturing method, and although U.S. Patent Application Publication No. 2006/0169998 has described its combination with a green phosphor having higher efficiency, no description has been given to the color reproducibility (NTSC ratio) thereof.
A red-color narrow band fluoride phosphor (KTF) exerts a red-color light emission with a peak wavelength of 635 nm and a spectrum half width of λ½=10 nm, which is extremely narrow, and has desirable light-emission characteristics for use in display applications; however, the fluoride phosphor (KTF) has a problem in that, when used as powder, it dissolves in water (solubility: about 1%) to generate hydrofluoric acid. When the powder is inhaled, bad effects are caused in the human body; therefore, sufficient cautions are required in handling the powder.